General SportbikesThis area is for sport bike discussion in general. Topics that don't really belong anywhere else can go here. Questions can be answered and addressed to fully understand certain aspects of the sport. If your question is manufacturer specific please post it there.
Sponsored by:
TCX Boots

This month I've been using this "Fuelly" app to track my mileage on the Ducati. Naturally, mileage was never a concern with this bike, but I was just curious, as I noticed it was using pretty much the same amount of fuel as my car.

Every fuel up I confirmed this, I was getting around 10km/l, or 24mpg, or so.

From what I've read, this is quite lower than usual on this bike, however given my context, I already expected some poor fuel economy (short trips, very cold weather, "fun" riding, etc). The thing is, while doing some maintenance I found that the PO had removed the original air filter screens (inside the intake runners) and had this big, really rough, dry and dirty air filter inside the airbox, covering the trumpets.

Old air filter:

We ordered the original air filters and removed that ugly piece of foam.

The oem filters:

We changed sparkplugs and the old ones had clear signs of rich fueling. At the same time we changed fuel filter, internal fuel lines, and fuel pump o-ring. And...this is when everything starts to happen.

Photo of fuel pump structure (notice that flange near the base...that's where the god damn fragile o-ring on which your safety and the bike's depend):

I notice inmediately that with the OEM air filter configurations, freeing up the airbox, the bike runs AMAZINGLY better. It already was a marvelous thing, but oh my god, now I understand what all that airbox rumble talk as all about. Everything feels right, so I expect at least a little improvement in fuel economy.

However, I get 7km/l on the next fuel up (16mpg or so)!!!

The bike rides amazing, so I start getting paranoid about a fuel leak. I smell the bike every time I get on or off...but I'm thinking perhaps it's my imagination. This is monday; tuesday morning I can't take it anymore so I go to my father's garage early before work.

I take the tank off, fuel pump assembly and yep, I have a fuel leak. It's a small leak coming from the fuel pump assembly base; it has produced this tiny fuel "pond" on top of the vertical cylinder.

I start checking everything, and all seems well. I'm in a hurry, need to get to work in 20 minutes or so (DO NOT WORK ON YOUR BIKE LIKE THIS!!!); I take the fuel pump out and find the big o-ring broken in 3. I can't believe...start panicking, I just ordered that one!

I go into the box of old parts and find the old o-ring...looks fairly good still, but as soon as I try it on, I confirm my suspicion that it had expanded way too much and it's no good now.

So, I guess this is my official welcome into Ducati ownership

Call my father and ask if I can take his KTM for the day. He agrees, so I take off and leave the Ducati waiting for me at the garage.

(A parenthesis to say that I am amazed by how nice this KTM Adventure 990 is. I hadn't ridden it in over a year. What a nice bike. I specially liked what is different to the Ducati: easy, instant, reliable starting; charging of the battery at idle, easy, friendly clutch.

It bloody rocks. Made me want to get a naked bike, something more "practical" as a second bike. I'm being honest here, I love the 916, but this feels like a back massage on wheels (and with lovely hard case).)

Last night, leaving the supermarket (yep, I said "night"; it's getting dark at around 23:00 here; gotta love the south pole haha)

But this morning I'm back with two new o-rings (in case I break another one) to install on the Ducati. I carefully install it, check thoroughly for leaks, everything seems ok.

Double and triple check that the "in" and "out" fuel lines are installed in proper order, and get everything back on the bike. I'm feeling happy, but the gas tank is almost entirely empty and the battery is lowish...

I make one of the worst decisions of this year, and push the bike outside, put my gear on, thinking "I better start it once only, and ride to the nearest gas station (couple miles), everything will be alright then". The idea was not to start it inside the garage and have to turn it off and restart outside (too much noise at that hour in the morning...

So there I go, close the gate and hop on my lovely italian steed. Ignition on, fuel pump primes, click the starter, and it turns and turns and turns without starting.

I figure fuel must not be getting to the system properly, so give it some gas. Nothing. Some throttle with the ignition on, waiting a few seconds, starting? Nope. Nothing.

So I get this brilliant idea: I'll push the bike down the hill and bump start it.

There I go, try it 4 times. NOTHING.

So, I end up 4 blocks from my father's, at the bottom of a pretty steep hill, with a dead bike.

Battery is not liking all these attempts, but my mind insists it's the fuel. Must be running too low for the pump (it has happened once).

It starts to rain, then some light snow, then some heavy rain. I'm wet and frustrated.

A gentleman appears from a house, he knows me from TV (I analyze MotoGP on local TV here), and he loves Ducatis, he brings back a tank with gas to give me. I thank him thoroughly, and he denies my payment. Very nice man. He asks me if I want a ride, I can leave the bike in his house, but I insist that the problem is fuel related, I'll fix it or push it back home.

3, 4, 5th try. Nope, NOT STARTING. Raining still, I give up and start to push the bike uphill.

Now, you need to understand this bike was made in 1995, I don't even know if it was light by the era's standards, but it weighs around 200 kilos dry. I'm getting a strenous workout, gasping and telling myself I shouldn't have praised the KTM's starting so much, this bike is really taking it out on me now.

But I finally get back to the garage. I'm all wet and sweaty, the bike is dirty, and I'm late for work. I get it inside, take the tank off and start inspecting everything, what the hell is going on?

...and then I see it.

Both, the feed and return lines from the tank have these plastic quick-connections. It turns out you really need to push them waaaay in for them to actually open proper flow. Way more inside than I had calculated...I had never even heard that loud "click" that confirmed my stupidity at this moment.

I carefully install the tank back on, put on the seat fairing.

Ignition on, fuel pump primes, I press the starter...

BROOOM BOOM BOOM BROOM (clackety clack clack clack clack) BRM BM BM

The loud roar fills up the garage, as I spontaneously scream "Gloria al Señor!!!!" (Praise the Lord). I can't believe my joy, or the fact that I somehow chose those words, given that I'm not a christian at all

I put on gear, roll the bike outside, cannot belive how nice this thing sounds (sorry KTM, your memory is starting to fade), it's still raining but I go out and I start to remember everything I love about this bike. How precise the throttle is, how hard but precise the clutch and transmission actions are, how the airbox sound makes you feel you're riding some kind of mad bull.

Man, I feel so good I don't even mind being so stupid about the fuel lines. I LOVE this bike.

Moral of the story: do your maintenance. You'll learn about your bike and yourself, you'll learn to understand better whatever happens to it, because you've experienced the causes to the symptoms. You'll save money, but most of all you'll enjoy it and learn a lot; and it will make the first ride after the service, so much better.

But pay attention. Work slowly if you need to. Take your time. DO NOT think "it'll just take 5 minutes and I head off to work"!!!

Yeah, I replaced that gasket on my BMW, then a month later I found out the fuel pump was bad, so I opened up the tank again. And then it turned out the tank was leaking. When I pulled out the pump to put it in the new tank, that O-ring had swelled up so much that I couldn't use it.

In just like 2-3 months. After 18 years I'd imagine it'd be pretty toast.

Most problems I have seen with motorcycles are because an owner/previous owner/mechanic has screwed something up. Every motorcyclist should have a Haynes or factory manual, proper tools including torque wrench, and an attitude of taking one's time to do the job carefully and methodically. You will then have the satisfaction of knowing the job is done right, and you will understand your motorcycle. Throttle body and fuel injection tuning requires more in-depth study but can be done by an owner with proper equipment. Often a lot of stuff has to be cleared away for access to the engine and it is no wonder that shops charge so much.

I lost that same exact O-ring. I carefully resolved the slight drip into a major gush. Inside my garage. With a full tank of gas. And the gas cap seal leaked, too.

I, unlike you, hated my 748 by the time I was done with it. World's most expensive SV650. . The fact that the bike is so easy to work on should have been my first clue!

KeS

hahaha that's so true. The fact that the bike is so friendly to take apart (10 dzus fasteners and two plastic security pins and all bodywork is out), and that there exist forums where people know EVERYTHING about fixing this bike, in so much detail that anyone who can follow directions can attempt it, should be a huge red flag

I empathize with your gas on garage experience...it's a terrifying situation, when you see the water falls coming. This time I had an almost empty tank.

Quote:

Originally Posted by kevinwilly

Yeah, I replaced that gasket on my BMW, then a month later I found out the fuel pump was bad, so I opened up the tank again. And then it turned out the tank was leaking. When I pulled out the pump to put it in the new tank, that O-ring had swelled up so much that I couldn't use it.

Ah yes, that's why I bought two of these not-proper-rubber-material rings. I'm fearing that if I have to take it apart again before the Vitton ones arrive, I'd be stuck with a swollen piece of rubber. Ugly stuff (although not as ugly as it sounds).

Quote:

Originally Posted by Wayne's Striple

Most problems I have seen with motorcycles are because an owner/previous owner/mechanic has screwed something up.

With this bike it has been like that. I've found a few hoses not inserted where they belong. The horrible air filter inside the airbox, the removal of the oem air filter screens and outside protection screens, the fact that last maintenance before we bought the bike was 2000 miles ago, or so, but that was 12 years before (!!!!!!!!, yeah, should've asked for more than simply "maintenance records"), the fact that he painted the mirrors and intake tubes green. But finally, the fact that he sold this bike for so little, never realizing it's one of the early hand built Varese units (made in Cagiva premises), that go for a slight premium... well, it was in need of some love.

Quote:

Originally Posted by Max Deutch

I am pleased to know that he is on TV analyzing MotoGP. Now that is really cool!

Thanks, my friend It's been really fun. I'm on the radio too, and now with the host of both shows we are launching a motorsport news website here (Patagonia Racing*|* if you are curious ).